An implementation of the SecretSealer abstract interface that binds the secrets to the enclave identity on a local machine. More...

#include <sgx_local_secret_sealer.h>

Inheritance diagram for asylo::SgxLocalSecretSealer:

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Collaboration diagram for asylo::SgxLocalSecretSealer:

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Public Member Functions
	SgxLocalSecretSealer (const SgxLocalSecretSealer &other)=delete

virtual	~SgxLocalSecretSealer ()=default

SgxLocalSecretSealer &	operator= (const SgxLocalSecretSealer &other)=delete

SealingRootType	RootType () const override
	Gets the sealing root type of this SecretSealer. More...

std::string	RootName () const override
	Gets the sealing root name of this SecretSealer. More...

std::vector< EnclaveIdentityExpectation >	RootAcl () const override
	Gets the sealing root ACL of this SecretSealer. More...

Status	SetDefaultHeader (SealedSecretHeader *header) const override
	Generates the default sealed-secret header based on the configuration of the SecretSealer and writes it to `header`. More...

StatusOr< size_t >	MaxMessageSize (const SealedSecretHeader &header) const override
	Gets the maximum message size (in bytes) that can be sealed according to the cipher-suite configuration recorded in `header`. More...

StatusOr< uint64_t >	MaxSealedMessages (const SealedSecretHeader &header) const override
	Gets the maximum number of messages that can safely be sealed according to the cipher-suite configuration recorded in `header`. More...

Status	Seal (const SealedSecretHeader &header, ByteContainerView additional_authenticated_data, ByteContainerView secret, SealedSecret *sealed_secret) override
	Seals the input per the header specification. More...

Status	Unseal (const SealedSecret &sealed_secret, CleansingVector< uint8_t > *secret) override
	Unseals the `sealed_secret` and writes it to `secret`. More...

Public Member Functions inherited from asylo::SecretSealer
	SecretSealer ()=default

virtual	~SecretSealer ()=default

virtual Status	Reseal (const SealedSecret &old_sealed_secret, const SealedSecretHeader &new_header, SealedSecret *new_sealed_secret)
	Re-seals an already sealed secret to a new header. More...

Static Public Member Functions
static std::unique_ptr< SgxLocalSecretSealer >	CreateMrenclaveSecretSealer ()
	Creates an SgxLocalSecretSealer that seals secrets to the MRENCLAVE part of the enclave code identity. More...

static std::unique_ptr< SgxLocalSecretSealer >	CreateMrsignerSecretSealer ()
	Creates an SgxLocalSecretSealer that seals secrets to the MRSIGNER part of the enclave identity. More...

Static Public Member Functions inherited from asylo::SecretSealer
static StatusOr< std::string >	GenerateSealerId (SealingRootType type, const std::string &name)
	Combines the specified sealing root type and sealing root name to form a string. More...

Detailed Description

An implementation of the SecretSealer abstract interface that binds the secrets to the enclave identity on a local machine.

The secrets sealed by this sealer can only be unsealed on the same machine.

The SgxLocalSecretSealer can be configured to seal secrets either to MRENCLAVE or MRSIGNER. The SgxLocalSecretSealer class provides two factory methods–one that creates an SgxLocalSecretSealer configured to seal secrets to MRENCLAVE and another that creates an SgxLocalSecretSealer configured to seal secrets to MRSIGNER. In the MRENCLAVE-sealing mode, the default SealedSecretHeader generated by the sealer binds the secrets to the MRENCLAVE portion of the enclave's identity. In the MRSIGNER mode, the default SealedSecretHeader generated by the sealer binds the secrets to the MRSIGNER portion of the enclave's identity. In either mode, the sealed secret is bound to all bits of MISCSELECT, and all security-sensitive bits of ATTRIBUTES, as defined in secs_attributes.h.

Note that the SealedSecretHeader provided to the Seal() method also controls the cipher suite used for sealing the secret. The default setting of this field (as populated by SetDefaultHeader() ) is subject to change. As a result, users must not make any assumptions about the default cipher suite. If they wish to use a specific cipher suite, they must manually verify or override the cipher suite set by the SetDefaultHeader() method.

Sample usage for Seal():

std::unique_ptr<SgxLocalSecretSealer> sealer = CreateMrsignerSealer();
SealedSecretHeader header;
// Fill out the portions of the header that must be set by the client.
header.set_secret_name("my name");
header.set_secret_version("my version");
header.set_secret_purpose("my purpose");
// secret_handling_policy is a client-specific string, which, for example,
could be a serialized proto.
string secret_handling_policy = ...
header.set_secret_handling_policy(secret_handling_policy);
sealer->SetDefaultHeader(&header);
// Override fields in the default header, if desired.
...
// Generate the secret to be sealed.
std::vector<uint8_t, CleansingAllocator> secret = ...;
// Generate the additional authenticated data to be tied to the secret.
string additional_authenticated_data;
addtional_authenticated_data = ...
// Seal the secret and the additional authenticated data.
SealedSecret sealed_secret;
Status status = sealer->Seal(header, additional_authenticated_data,
                             secret, &sealed_secret);

Sample usage for Unseal():

std::unique_ptr<SgxLocalSecretSealer> sealer = CreateMrsignerSealer();
SealedSecret sealed_secret;
...
sealed_secret.ParseFromString(...);
std::vector<uint8_t, CleansingAllocator<uint8_t>> secret;
ASYLO_RETURN_IF_ERROR(sealer->Unseal(sealed_secret, secret));
// secret now holds the unsealed secret. The policy and
// additional_authenticated_data in the sealed_secret are now
// authenticated.

It should be noted that the SgxLocalSecretSealer's configuration only affects the default header generated by the sealer. Users can override the generated default header. A sealer in either MRENCLAVE or MRSIGNER configuration can unseal secrets that are sealed by a sealer in either configuration.

Constructor & Destructor Documentation

◆ SgxLocalSecretSealer()

asylo::SgxLocalSecretSealer::SgxLocalSecretSealer ( const SgxLocalSecretSealer & other )

delete

◆ ~SgxLocalSecretSealer()

virtual asylo::SgxLocalSecretSealer::~SgxLocalSecretSealer ( )

virtualdefault

Member Function Documentation

◆ CreateMrenclaveSecretSealer()

static std::unique_ptr<SgxLocalSecretSealer> asylo::SgxLocalSecretSealer::CreateMrenclaveSecretSealer ( )

static

Creates an SgxLocalSecretSealer that seals secrets to the MRENCLAVE part of the enclave code identity.

Returns: A smart pointer that owns the created sealer.

◆ CreateMrsignerSecretSealer()

static std::unique_ptr<SgxLocalSecretSealer> asylo::SgxLocalSecretSealer::CreateMrsignerSecretSealer ( )

static

Creates an SgxLocalSecretSealer that seals secrets to the MRSIGNER part of the enclave identity.

Returns: A smart pointer that owns the created sealer.

◆ MaxMessageSize()

StatusOr<size_t> asylo::SgxLocalSecretSealer::MaxMessageSize ( const SealedSecretHeader & header ) const

overridevirtual

Gets the maximum message size (in bytes) that can be sealed according to the cipher-suite configuration recorded in header.

The user is expected to call this before calling Seal() to ensure that they have chunked their messages correctly. The maximum message sizes of supported cipher-suites are as follows:

AES-GCM-SIV supports a maximum message size of 32 MiB

Parameters

header The associated header to determine the maximum message size.

Returns: The maximum message size that can be encrypted based on the cipher-suite configuration in header, or a non-OK status if the

Implements asylo::SecretSealer.

◆ MaxSealedMessages()

StatusOr<uint64_t> asylo::SgxLocalSecretSealer::MaxSealedMessages ( const SealedSecretHeader & header ) const

overridevirtual

Gets the maximum number of messages that can safely be sealed according to the cipher-suite configuration recorded in header.

The user is responsible for following these guidelines. The secret sealer will not check the number of secrets sealed. The maximum number of sealed messages of supported cipher-suites are as follows:

AES-GCM-SIV can safely seal 2 ^ 48 messages

Parameters

header The associated header to determine the maximum number of sealed messages.

Returns: The maximum number of messages that can be sealed based on the cipher-suite configuration in header, or a non-OK status if the cipher-suite configuration is not supported.

Implements asylo::SecretSealer.

◆ operator=()

SgxLocalSecretSealer& asylo::SgxLocalSecretSealer::operator= ( const SgxLocalSecretSealer & other )

delete

◆ RootAcl()

std::vector<EnclaveIdentityExpectation> asylo::SgxLocalSecretSealer::RootAcl ( ) const

overridevirtual

Gets the sealing root ACL of this SecretSealer.

Returns: The sealing root ACL of this object.

Implements asylo::SecretSealer.

◆ RootName()

std::string asylo::SgxLocalSecretSealer::RootName ( ) const

overridevirtual

Gets the sealing root name of this SecretSealer.

Returns: The sealing root name of this class.

Implements asylo::SecretSealer.

◆ RootType()

SealingRootType asylo::SgxLocalSecretSealer::RootType ( ) const

overridevirtual

Gets the sealing root type of this SecretSealer.

Returns: The sealing root type of this class.

Implements asylo::SecretSealer.

◆ Seal()

Status asylo::SgxLocalSecretSealer::Seal	(	const SealedSecretHeader &	header,
		ByteContainerView	additional_authenticated_data,
		ByteContainerView	secret,
		SealedSecret *	sealed_secret
	)

overridevirtual

Seals the input per the header specification.

The header must have its secret_name, secret_version and secret_purpose fields populated. If any of the remaining fields in the header are populated, then they must be compatible with the underlying sealing root.

Parameters

	header	The metadata to guide the sealing.
	additional_authenticated_data	Unencrypted data that is bundled with the sealed secret.
	secret	The data to encrypt and seal.
[out]	sealed_secret	The output sealed secret.

Returns: A non-OK status if sealing fails.

Implements asylo::SecretSealer.

◆ SetDefaultHeader()

Status asylo::SgxLocalSecretSealer::SetDefaultHeader ( SealedSecretHeader * header ) const

overridevirtual

Generates the default sealed-secret header based on the configuration of the SecretSealer and writes it to header.

Parameters

[out] header The destination for the default SealedSecretHeader value.

Returns: A non-OK status if a default cannot be set.

Implements asylo::SecretSealer.

◆ Unseal()

Status asylo::SgxLocalSecretSealer::Unseal	(	const SealedSecret &	sealed_secret,
		CleansingVector< uint8_t > *	secret
	)

overridevirtual

Unseals the sealed_secret and writes it to secret.

Parameters

	sealed_secret	The input secret to unseal.
[out]	secret	The destination for the unsealed secret.

Returns: A non-OK Status if unsealing fails.

Implements asylo::SecretSealer.

The documentation for this class was generated from the following file:

asylo/identity/sealing/sgx/sgx_local_secret_sealer.h

Public Member Functions

Static Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ SgxLocalSecretSealer()

◆ ~SgxLocalSecretSealer()

Member Function Documentation

◆ CreateMrenclaveSecretSealer()

◆ CreateMrsignerSecretSealer()

◆ MaxMessageSize()

◆ MaxSealedMessages()

◆ operator=()

◆ RootAcl()

◆ RootName()

◆ RootType()

◆ Seal()

◆ SetDefaultHeader()

◆ Unseal()